That is the short version. The longer truth is that August is the month when the garden either coasts or collapses, and the difference is almost entirely down to water and picking. I have had Augusts in Oxfordshire where I went away for a fortnight and came home to bolted lettuce, split tomatoes and courgettes the size of my leg, and Augusts where twenty minutes a day kept the whole plot ticking over beautifully. This is my honest list of what actually needs doing this month, roughly in order of importance, and the jobs you can safely ignore.

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Keep on Top of Watering

Watering is the job that decides August. The beds are full, the plants are at maximum size and thirst, and the rain often is not coming. Water deeply two or three times a week rather than a little every day, because a proper soak pushes roots downwards while a daily sprinkle keeps them at the surface where they cook. Do it in the early morning or the evening so less is lost to evaporation, and aim the can at the base of the plant, not over the leaves.

The priority list when time or water is short: anything in a container first, because pots can dry out in a single hot day, then tomatoes, courgettes, beans and anything swelling fruit, then recent plantings. Established shrubs and lawns come last and will generally cope. Inconsistent watering is behind most of the August disasters people blame on disease, from split tomatoes to blossom end rot, and my guide to how often to water plants in the UK covers the details, along with the watering mistakes that quietly stress plants.

Harvest Little and Often

August is peak harvest, and the single most productive thing you can do is pick every day or two. Courgettes, beans, tomatoes and cucumbers all work on the same rule: the more you pick, the more the plant produces, because its whole aim is to set mature seed. Leave a courgette on the plant for a week and it becomes a marrow, and the plant slows right down thinking its job is done.

Runner and French beans want picking while the pods still snap cleanly. Tomatoes are best taken as they colour rather than left to hang, which also reduces splitting after rain. If your tomato plants are covered in flowers but nothing is setting, that is a common August complaint with a few specific causes, and I have covered them in why tomato plants stop producing fruit. Second early and maincrop potatoes are also ready to start lifting this month, so ease a root up and see what is under there.

Feed the Plants Still Working Hard

Anything producing fruit in a pot or growbag is running on empty by August and needs a weekly liquid feed, tomatoes especially. A high-potash tomato feed does the job for peppers, chillies, cucumbers and aubergines too. In open ground the need is less urgent, but heavy croppers still appreciate a fortnightly feed while they are producing.

Stop feeding permanent shrubs and roses by the end of the month though. Feeding late into the season pushes out soft new growth that will not harden before the first frosts, and it gets burned off in October. August is the last call for feeding anything woody.

Summer Prune Fruit, Hedges and Lavender

August is the traditional month for summer pruning trained fruit. Apples and pears grown as cordons, espaliers and fans get their new side shoots shortened now, which lets light onto the ripening fruit and keeps the shape tight. Summer-fruiting raspberries that have finished cropping want their old canes cut to the ground, keeping this year’s fresh green canes for next summer. Blackcurrants, gooseberries and cherries can also be tidied after fruiting. The Royal Horticultural Society has a good rundown of the method on its apple pruning and training pages.

It is also the month to trim lavender, once the flowers fade. Cut the flower stalks off and take a couple of centimetres of the leafy growth with them, but never cut back into the old bare wood, because lavender rarely regrows from it. I shear mine into tidy green mounds in late August and they hold that shape through winter, and there is a full guide in how to grow lavender in the UK. Hedges can have their last proper cut of the year now too, after checking for any late bird nests before you start.

Deadhead and Keep the Flowers Coming

Five minutes of deadheading every couple of days keeps dahlias, roses, sweet peas, cosmos and bedding flowering into October. The logic is the same as picking beans: stop the plant setting seed and it keeps producing flowers instead. Sweet peas in particular must be picked or deadheaded constantly, because the moment they set a pod the display is over.

The exception is anything you want seed or autumn interest from. I leave the last flush on my roses for hips, and seedheads on fennel, teasels and sunflowers stand handsomely into autumn and feed the birds. Deadheading is a job to do with a drink in your hand on an August evening, not a chore to schedule. BBC Gardeners’ World has a useful primer on the technique for different flower types in their deadheading guide.

Sow Now for Autumn and Winter

The sowing year is not over, and August is the month for starting the crops that carry you through autumn and winter: fast salads and radishes, spinach and chard, pak choi and oriental leaves, spring onions, and spring cabbage for that first fresh picking next March. Warm soil means everything germinates in days, and the cooling nights suit exactly the crops that bolt in high summer.

I have written the full month’s sowing list up separately in what to sow in August in the UK, including the drill-watering trick that stops late-summer sowings failing in dry soil. If you only do one sowing job this month, get spinach in, and my guide to how to grow spinach in the UK covers it from there. For timing anything else, the UK Vegetable Planting Calendar shows the whole year at a glance.

Look After the Greenhouse

Greenhouses cook in August. Open every vent and the door on hot days, damp down the path with a can of water in the morning to raise humidity, and keep shading in place. Red spider mite thrives in hot dry glasshouse air and can wreck cucumbers and aubergines in a fortnight, and humidity is your main defence against it.

Keep pinching out tomato side shoots and, towards the end of the month, take the top out of each plant a couple of leaves above the highest flowering truss. It feels drastic, but it sends the plant’s energy into ripening the fruit it already has rather than making more that will never mature. Anything still stubbornly green by the end of the season can be ripened indoors. The side-shoot job is quick once you have the knack, and removing tomato side shoots shows exactly where to pinch.

Water Butts, Ponds and Wildlife

Keep bird baths and any shallow water topped up, because natural water is scarce for wildlife in a dry August and a saucer of water does more good this month than a feeder. Ponds evaporate fast, so top them up little and often, ideally from a water butt rather than the tap. If a hosepipe ban arrives, and August is when they do, grey water from washing up is fine for ornamental beds in the short term.

It is also worth letting a corner stay slightly untidy. Long grass, a log pile and standing seedheads shelter the frogs, beetles and hoverflies that quietly eat your pests, and Garden Organic explains how to put these natural allies to work in their wildlife gardening advice. The slugs certainly do not take August off, and if they are hammering your new sowings, how to get rid of slugs in the UK covers the defences that actually work.

Jobs You Can Skip in August

Do not plant new shrubs, trees or perennials now unless you enjoy watering them twice a day, because August-planted stock struggles in hot dry soil and the same plant put in during autumn will establish far better. Do not lay turf or sow a new lawn, for the same reason. Leave the existing lawn slightly long in dry spells rather than scalping it, and do not panic when it browns off, because it recovers with the September rain every single time.

Major pruning of spring-flowering shrubs is also best left alone now, as they have already set next year’s flower buds and cutting them means cutting the display. And resist tidying too hard generally. August untidiness feeds a lot of garden life, and the big autumn sort-out is only weeks away anyway. Before then, it is worth planning sowing in September so beds do not sit empty.

Common Questions About August Gardening Jobs

A Sensible Place to Start

If the list feels long, it boils down to a simple daily loop: twenty minutes each evening with a watering can and a trug, picking what is ready, pulling the odd weed, and deadheading as you pass. Do that most days, get one decent sowing of spinach or salads in, and give the lavender its trim before the month is out. That is a well-run August.

This piece follows on from June gardening jobs in the UK and May gardening jobs in the UK in the monthly series, and pairs with what to sow in August in the UK for the full sowing side of the month. September brings the start of the autumn planting season, and with it a very different jobs list.

Here in Oxfordshire I treat the second half of summer as a quiet second season. Beds that have given up their broad beans or early potatoes don’t need to sit bare until next year. There’s a surprising amount that will still germinate, grow, and crop before or through the colder months, and a few things that want sowing now precisely because they need the long, slow start. Below is what I actually sow in August on my own plot, why, and the bits that catch beginners out.

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What August Sowing Is Really For

The mental shift that helps is this. In April and May you sow for the summer plate. In August you sow for three different timelines at once: fast crops to fill the gap right now, hardy crops to carry you through autumn and into winter, and a handful of things that want sowing in late summer so they’re well established before the cold arrives. Once you think in those three buckets, the whole month makes sense.

Warm soil is the great advantage. Seeds that sulked in a cold April seedbed will be up in days now. The thing working against you is dryness, because August beds can bake hard, so watering the drill before you sow matters far more than it did in spring. I’ll come back to that, because it’s the single biggest reason late-summer sowings fail.

Salad Leaves You Can Keep Sowing

Salad is the easiest win in August and the one I’d start with if you only do one thing. Lettuce sown now crops into autumn, and because the worst of the summer heat is passing, it’s far less likely to bolt than the batches you sowed in June. For the full sowing windows across the year, see my lettuce sowing calendar. I sow a short row of loose-leaf lettuce like ‘Salad Bowl’ or ‘Lollo Rossa’ every couple of weeks so there’s always something to cut rather than a glut all at once.

Rocket comes into its own now too. It bolts almost on sight in high summer, but an August sowing in cooler conditions stays leafy and useful for weeks. The same goes for mizuna, mustard leaves, and the looser oriental salad mixes. These are cut-and-come-again crops, so one sowing keeps giving. If you want a proper steer on successional salad timing, the Royal Horticultural Society has a clear guide to sowing salad leaves through the season at the RHS salad leaves page.

Fast Crops: Radishes, Spring Onions and Turnips

If a bed has just come empty and you want it earning its keep again quickly, this is the group to reach for. Radishes are the fastest thing in the vegetable garden and will be ready in three to four weeks from an August sowing, which means you can squeeze a full crop in before the season turns. Sow them thinly, because crowded radishes go to leaf and never bulk up properly, a mistake I made for years before I learned to thin without sentiment.

Spring onions sown now will stand into autumn and some varieties, like ‘White Lisbon Winter Hardy’, will overwinter for an early pull next year. Turnips are the underrated one here. An August sowing of a quick variety such as ‘Snowball’ gives you tender, golf-ball-sized roots in autumn that taste nothing like the woody supermarket version. They want consistent moisture, but they’re genuinely fast and forgiving.

Oriental Leaves and Pak Choi

Pak choi is one of those crops that almost demands to be sown late. Sow it in spring or early summer and it bolts the moment it gets warm and stressed, which is maddening when you’ve watched it grow nicely for a fortnight. Sow it in August into cooling conditions and it behaves itself, forming proper plump heads. The same is true of choi sum, tatsoi, and Chinese cabbage.

These oriental brassicas are quick, they’re happy in a bit of shade if your August beds are still catching strong sun, and they shrug off the cooler nights that are coming. Watch for flea beetle, which peppers the leaves with tiny holes. A layer of fine mesh over the row early on is the simplest defence and saves a lot of nibbled, lacy leaves.

Spinach and Chard for the Cooler Months

True spinach is a cool-season crop at heart, which is exactly why August suits it. A sowing now establishes through autumn and, with a bit of protection, will give you pickings well into winter and a flush again in early spring. Sow a variety described as hardy or for autumn use, water the drill well, and keep it picked over rather than letting the leaves get large and bitter.

If you’ve never had luck with spinach bolting on you in summer, an August sowing is the answer. Perpetual spinach and chard are even more reliable and tougher through cold weather. Chard in particular is one of the most generous things you can grow over winter, standing through frost on my clay and cropping when little else will. One late-summer sowing of chard genuinely earns its space for the best part of a year.

Spring Cabbage and Crops to Overwinter

This is the part of August sowing that beginners most often miss, and it’s the one with the longest payoff. Spring cabbage is sown now, in late summer, to grow into small plants before winter, sit through the cold, and then romp away to give you fresh greens in the hungry gap of March and April when almost nothing else is ready. Sow into a seedbed or modules in August, transplant in autumn, and you’ll be cutting tender spring greens when the shops are still selling tired imports.

It’s the same logic as autumn-planted garlic, which goes in soon after this and overwinters in the same way. If you haven’t grown garlic before, it’s one of the easiest overwintering crops there is, and I’ve written up the whole process in my guide to how to grow garlic in the UK. Lamb’s lettuce, also called corn salad, and land cress are two more hardy salads worth sowing now for winter cutting, both of which laugh at frost.

Herbs That Still Have Time

Coriander is the obvious one. Like rocket and pak choi, it bolts in the heat of summer and runs to seed before you’ve had a decent picking. August’s cooler nights are exactly what it wants, so a late-summer sowing gives you the longest run of leaf you’ll get all year. Sow it where it’s to grow rather than transplanting, because it hates root disturbance, and keep it cut. There’s more detail on getting it right in my full guide to growing coriander in the UK.

Parsley sown now will establish before winter and stand for fresh picking through the cold months and into a second year. Dill and chervil are both happy with an August start too. These are the herbs that actually prefer the shoulder of the season rather than high summer, so don’t write them off just because the main herb-sowing window feels like it’s behind you.

Green Manures for Beds You Have Cleared

If a bed comes empty and you’ve nothing to sow into it, don’t leave bare soil to bake and wash away over autumn. Sow a green manure instead. These are fast-growing cover crops you sow to protect and improve the soil, then dig in or cut down before they flower. Mustard is the quickest and germinates almost overnight in warm August ground. Phacelia is my favourite for late summer because it’s pretty enough that the bees find it before you turn it in.

Field beans and grazing rye can also go in a little later and will hold the soil right through winter. The point of all of them is the same: keep the ground covered, feed the soil structure, and smother weeds while a bed would otherwise be idle. Garden Organic has a thorough rundown of which green manure suits which situation at their green manures guide, and it’s worth a read if you’ve never used them.

Hardy Annuals and Sweet Peas for Next Year

It’s not all vegetables. Some of the best hardy annual flowers actually want sowing in late summer or early autumn rather than spring, because the young plants overwinter as sturdy little clumps and then flower weeks earlier and far bigger than anything you sow next March. Calendula, cornflowers, larkspur, poppies, and ammi all respond brilliantly to an autumn start. I scatter them into a corner of the veg beds and barely think about them again until they put on a show.

Sweet peas are the standout. Sown in late August or September and overwintered in a cold frame or unheated greenhouse, they build a strong root system and reward you with earlier, more abundant flowers than a spring sowing ever will. If you only try one autumn-sown flower, make it sweet peas. The team at BBC Gardeners’ World explain the autumn sowing approach well in their guide to sowing sweet peas.

Getting Seeds to Germinate in Late Summer Heat

Here’s the bit that decides whether any of this works. August soil dries out fast and bakes into a crust that seedlings struggle to push through. The fix is simple and I do it without fail now. Draw out your drill, water along the bottom of it generously, let it soak in, then sow into the damp and cover with dry soil. The seed sits in moisture while the dry cap on top stops the surface crusting. It feels back to front the first time you do it, but it transforms your strike rate.

Keep things shaded for the first few days if the sun is fierce. A length of fleece, a plank laid over the row until you see the first shoots, or simply sowing in the cooler part of the day all help. And keep the watering steady, because the most common reason an August sowing fails isn’t cold or pests, it’s a row that germinated and then dried out the moment you looked away. If you want a refresher on the basics of getting seed up reliably, my guide to growing vegetables from seed in the UK covers it from the start.

Common Questions About Sowing in August

A Sensible Place to Start

If August feels like a lot of options, narrow it right down. Sow a row of salad leaves and a row of radishes this week for something quick, get spinach or chard in for the colder months ahead, and start a tray of spring cabbage for that early greens crop next year. That’s three sowings covering all three timelines, and it’s plenty to be getting on with. If the seed tin is missing any of them, Thompson and Morgan’s vegetables to sow in August page carries the lot. And for everything beyond the sowing, from watering to summer pruning, August gardening jobs in the UK covers the rest of the month’s work.

From there, build out as beds clear. For a quick visual of when every crop wants sowing and harvesting across the year, keep my UK Vegetable Planting Calendar handy. This sits naturally alongside the previous month, so it’s worth a glance back at what to sow in July to see what still has time, while how to grow spinach in the UK and when to plant cabbage in the UK cover two of the best August sowings in full.